3-D Design Software and Honkey Dory Keel Heights

Sandy and those interested in the white water dory design dialogue (alliteration anyone?),
I started messing around with 3D design software. My requirement was that it should be free. That leaves me Sketch Up and Free!Ship. Free!Ship (available at SourceForge and C-Net) is the leader at this point. It runs on all versions of Windows (I am running it on Windows 10 on an old laptop proving you don't need much horsepower). Long and short of all this is that my buddy got the Briggs Dory from Roger's Book rendered in the software in about 20 minutes. I on the other hand am working to render the Honkey so we can scale it up and compare etc. We will also render some scaled up McKenzies for visual comparisons. Free!Ship also looks like it has the ability to render 2-d printouts of side panels etc (let's you flatten your model). I am really stoked to try some rapid model building e.g. print the side panels at a particular scale, use it as a template to cut sign material, affix to a stem, glue up a transom and add the bottom. Bingo. It would be sweet to have a scale Honkey, McKenzie, and Briggs sitting on my desk to putz around with and ponder their merits.

All that aside, Sandy what are the heights from zero of the "keel" of the Honkey? Station 5 is the center of the boat and I assigned it a height of zero. What is the rocker height at the stem and at the transom with your standard transom? If you would share those values and if you have them at each station we can pop out stuff like this pretty quick. This is the Briggs loaded with 1000lbs, they grey portion is under water:

Wish I could help. That looks like good software. I'll have to download it and try it out. i have a project on Sourceforge--Robopages--the software that generates this website (although not this forum....which I need to change. Robopages runs everything else). I love open source stuff that works.

My plans work by marrying rib-like trapezoid shapes to side panels of specified dimensions, at specified layout locations. Those dimensions work for building the boat but they probably won't work for setting up nurb curve point locations in anybody's 3D software.

And I can't go out to measure because I sold my last HD a few years ago. I do wish I had one back. My current boat is a relatively flat bottomed boat that works well with my 20hp Merc. But it rows like an arthritic dog compared to the old HD.

Maybe what you really want to do is to design your own boat. Using HD ideas as a conceptual starting point.

The HD grew out of the old McKenzie River tradition where one or two passengers sit on the front seat immediately in front of the rower. That arrangement places the bulk of the payload as close to the boat's center of gravity as possible. That makes the fastest, best handling 3 person dory possible. As an outgrowth of that tradition McKenzie style boats tend to be somewhat pear shaped in the plan view, looking down, where the front is a bit wider than the rear. That's because the rear doesn't carry any weight. Not counting the Briggs every other boat in Roger Fletcher's dory book reflects that shape. Most or perhaps even all the boats in his book (not counting the Briggs) don't even show a seat behind the rower.

I wanted to build the world's best McKenzie style boat. I made it a lot wider than any Oregon boat, at least in relation to its length. But kept all else much the same. I wanted to have my cake and eat it too payload wise. I wanted to be able to put a rear-positioned fly fisherman in the boat if I wanted. That payload spreads the weight out so it isn't ideal for really big water. But I wanted to accommodate both situations. So I made the front deck much smaller and placed all seats on rails, so the seating positions could slide way forward when in fly fishing mode, so the boat would still trim properly. Surprisingly few Oregon boats handle well at all when used in fly fishing mode.

And then to slide the seats back again when in white water or bait fishing mode, where the passengers sit on the front seat.

So far so good. The Briggs is way way narrow in relation to its considerable length. And most Briggs boats put the passengers (as many as four with two in the front and two in the back) at the ends. That's not ideal for white water. Not if you believe in the traditional McKenzie concept. The best handling boat in BIG water puts the payload as close to the center of the boat as possible. Do you really want 4 passengers? Put them in two rows of side-by-side seats slightly forward of the middle of the boat, with the rower behind that. Now all the weight is as close to the center of the boat as possible.

You can test this idea in almost any boat. Put three people as close to the rower's seat as possible, leaving juuuuuust enough room for the actual rower to pull the oars. Row it that way. Now put the two passengers as far apart as possible, one in the way front and one in the way back. Now the boat is way way harder to row. And noticeably more side-to-side tippy. Spreading the payload out is flat out wrong. At least is superior handling in big water is your goal.

I'll never build any boat that is narrower in the rear again. The HD is a great boat. But I'm moving on now and anything I ever build from here on out will be symmetrical, where two feet forward of the rower has the same width as two feet back. The rocker profile can change.. I like more rocker at the upstream end and less at the downstream end. But I like the width to stay the same.

The best big water boat has not yet been built. The Briggs is too narrow. Way too narrow. At least in relation to its length. I don't like its rocker profile either. I like almost flat in the middle. But not dead flat as a board flat.

The best big water boat would be wide with a bit more rocker upstream than down, but with a symmetrical width profile. Almost but not quite flat in the middle with a lot more rocker out toward the ends. And built so the payload is as close to the center of the boat as possible. Lots of side flare in a way that does not create too much rocker. Which means dish out the chine. A widely-flared boat looks like a ridiculous banana, if it has a straight line chine.

On the keel heights I almost have them. My Honkey is down in Reno with my good friend who is getting ready to paint it for me. I got surprising close without the actual measurements in my draft model. The only ones I really need to buff this model is the rocker at the stem and transom and Pat is out measuring them. We'll nail this model and post it this afternoon. The software is as simple as can be. If you want to model interior parts and decking, it looks like it will work well for that. If not I can bring it into Sketch Up once it is to scale.

I learned a lot today converting your plans to an offset table for the "keel", chine, and sheer. It gives me another view and an additional understanding of your hull that I constructed. It was a great exercise for me mentally. Doing that with the other designs will help me learn a lot. Then the HUGE benefit to me that I can screw around with the offset table and add two feet to the Honkey, add width to the bottom and make the bottom of the Honkey symmetrical. I can fatten a Briggs and give it a dished chine etc. etc. etc. Since I don't have a heated shop I can fool around with the design in 3-D and play with increasing the rear rocker and decreasing the front rocker some on the various dories. Then I print out the side panels in 1/12 scale and see how it looks!

You nailed it, we want to build our own design and looking at the Briggs (mostly for aesthetics), Honkey, and various McKenzies we will putz around with until we nail our design down. One fun thought we are kicking around is that Pat wants to build frames and go with a full traditional build and I am going 100% Plascore over a male plug. We are thinking about building the same exact design but with the two different techniques.

As of now my punch list for my dory includes:
wide
symmetrical bottom
dished chine
variable rocker fore to aft
around 17-ish feet, maybe 18.
exceeding 60" in width
Not exceeding 88" at the oarlocks (this is where I can model the crap out of that problem)
have just the right amount of flare
100% Plascore for sides, bottom, decks, and lids
somewhere around 66-71 oz of "glass" on the bottom

I will be reviewing the great threads here on lay up with the take away that more on the outside is better and keep in interior simple with some 10 oz and layer of kevlar for the inside. I remember a thread that laid out the benefits of using some polyester in the layup. What a fun way to spend a fall day where it is dumping snow outside my window!!!

Here is the Honkey Dory. The software has some great features! For example you can place a given mass in the boat and it shows displacement. Sandy, you list the Honkey as good at 1,100 pounds. Here is the boat at 1,150 pounds and note that the transom is high and dry! You can make a table that shows draft vs. weight in the boat etc. So you can look at say the Briggs above vs. the Honkey and see what each drafts for a given load. Now this isn't a number I would bet anyone's safety on, but for comparative purposes it looks to a great tool! See the table below. I'll goof around with this more later and send you the offset table if you want to play with it of host it.

Here's a different take of designing, lofting and building a new big water boat. Brad Dimock from Flagstaff has spent a fair amount of his life rowing big water and building boats. Anyway starting on the page below is his newest build and a few words and pictures on how he designed the latest boat. It's good to have a variety of options when you design and build something new to my way of thinking.

One picture along the way shows how a dished panel actually looks when cut. I am intrigued by this latest build and hope to follow it to observe the on-water results. From what I read Brad didn't think it would be dished but it works fine to replicate the model the client chose.

Yes the new Brad Dimock boat is interesting. He "widened it (the Briggs) 14%" which means it's a 54" wide boat. Apparently lengthened the boat a bit too (even longer than the Briggs).

So this is a completely new boat for sure. The traditional McKenzie boats started off as roughly 15' feet long and 48" inches wide. If you scale one of those up proportionately, to make a seventeen footer you get a 17x54. Which is what nearly all 17' foot Oregon boats are.

Brad's boat is a strong 18' feet long and 54" inches wide. So it's still relatively narrow as width to length ratio. At least when compared to an HD, which is a bit wider and substantially shorter.

The MRB Honky Dory is a 15' long foot boat at 56" inches wide! That is a step away from the norm. Scaled up to 17' feet you get a boat over 60" inches wide. That's what I'm building now. A 63" wide 17' footer. It won't be an HD because I'm flaring the side out more and making it wider at the upstream end than the original HD. But it will be wide.

The only other extra wide boats I know of were built by Cyrus Happy. Ray Heater's partner for many many years. I've rowed one of those wide wide Cyrus Happy boats. Rows like a dream for its size. When I tell people I'm building a 63" wide boat many of them roll their eyes and immediately ask questions about "how wide is too wide?"

But you have to remember. Wide dories already exist. A few of them anyway. And everybody smiles the minute they get their hands on the oars.

I would be better advised to shut up at this point. But I can't stop. :=)) This is my favorite subject.

The original McKenzie boats have been called an example of "form follows function." But they can also be seen as an example of form follows material convenience. The first McKenzies were made with side panels cut from 4x16 because that's what you get from two sheets of plywood. Same reason they were 48" inches wide. They're good boats and everybody loved them. But that doesn't in any way mean 15x48 is ideal.

Wider, in fact, turns out to be substantially better. The first Grand Canyon Dories (Keith Steele Suzie Two and Jerry Briggs' version) were 48" inches wide because those two guys didn't have their heart in the project and they wanted to make something as fast as possible. So they chopped a 15x48 in half and added a dead flat 48" wide tunnel in between the two halves.

I've never rowed the Grand Canyon so I can't say what is best and what isn't. But I have rowed the Briggs and I didn't like it. It's hard to turn and so side-top-side tippy it makes you sea sick. There is a reason nobody rows it any where else. Oh you do see a few on the Green or the Yampa. San Juan. But those are easy to row rivers, even at Memmorial Day. There aren't any Briggs on the Middle Fork of the Salmon. They wouldn't survive. Because they are so narrow in relation to their length they sink deeply into the water, which makes it impossible to dodge around rocks.

For a 15' foot long boat what is the ideal width? I don't know. I've tried 48 and 56 (for a 15 footer mind you) and 56 is far better. Would 54" inches or 58" be better yet? I don't know. I haven't built it. But I strongly suspect 58" inches would row the pants off 54.

This is an awesome conversation! Really a breakthrough honestly. I am e-mailing Sandy the offset tables for the Honkey (stock) and Briggs (from Fletchers book). I developed the offsets for the Honkey from Sandy's plans and got pretty close. My boat building partner has my Honkey and he measured the chine elevations and trued up sheer elevations which started from Sandy's station heights added to the keel heights. I was close, but the rocker wasn't right. In plan view it was nearly perfect, but the sheer elevation was screwed up and looked like a sardine. Well the measurements from the boat solved that. Now I am at a place where I want to modify these models but I am going to step back put together the models for the Woody's original McKenzie Double Ender, Woody's 16 Foot Rouge Double Ender, and the original McKenzie with a transom, and the Classic Rouge River Dory. Why? Why not.

One interesting comparison is to plot draft vs. displacement of the Honkey and the Briggs. When you look at those curves they look close but you have to recall the Briggs is 18'. To a point Sandy makes narratively by sharing his experience of rowing different width boats we can look at some numbers that support his take aways. One is length length measured at waterline for each boat. For example the Briggs and the Honkey loaded to where each is drafting 5.5" of water (shown below) the Honkey is holding 772 pounds while Briggs is only holding 800 pounds. The Briggs has 11.36' length measure at the waterline while the Honkey only has 10.16'. The images below show each of the boats in the condition described above. Note how the shading depicts what is in the water. I especially like the top down view showing how much of the bow and stern is above the water.

They're around. Every year I see my boats on the river. Some of them 20 years old. Or more. But I never know who owns them. They trade hands every five years or so. I saw a Beavertail in a TV commercial about fly fishing on the Bow River in Alberta once. I was in a convenience store in Medicine Hat and I started pointing at the TV telling everyone to look. They all thought I was nuts.

I'll see if I can contact Roger Daniel. He's a cabinet maker who built one of the prettiest Beavertails ever. A few years back.

OK....this free program is the absolute BOMB! I used the Develop Plates (panels) function and it unfolds the model from 3D and transforms to 2D in what is essentially a cut pattern! So the floor I don't care too much about but it will help in making a bill of materials. I unfolded the Briggs and I can see a few station lines that need to be cleaned up. Another thing I learned is to set the water density to the freshwater value of 62.4 pounds per cubic foot. Free!Ship defaults to the saltwater value of 64 pounds per cubic foot. So unless you switch it, all hydrodynamic and hydrostatic calculations will be off. e.g. you'll draft more water than you think you will for a given load.

FREE!ship and Linux.
Free!ship is originally intended for Windows, although users have reported that it runs rather well
under WINE too. In some cases problems might be experienced with the window focus. In Windows
the dialog that has focus always stays in front of the mainform. Under Wine the dialog windows of
FREE!ship go sometimes to the background while retaining user input focus. As a result, FREE!ship
seems to be crashed while it hasn't. To solve this problem, you must cycle through the windows to
get the dialog window back to the foreground and close it. Unfortunately, some window managers
don't allow this because not all of the open windows are listed in the window menu. The following
are the results of some tests that have been done on a Ubuntu Breezy Badger.
KDE 3.5 Unusable. The menus don't stay opened so no menu item can be chosen.
Gnome Only the main window of FREE!ship is listed in the window menu, so if you
loose the focus of a dialog window, your only choice is to kill FREE!ship.
Fluxbox OK
IceWm OK
WindowMaker OK
Openbox OK
Blackbox Not tested, but as Blackbox is quite close to Fluxbox it is probably ok.

Your dbm files load up just fine in FreeShip. I tried some open source hull modeling software 4-5 years ago and gave up in disgust. It was too cumbersome. I realize Rhino is really good software but I can't afford it.

FreeShip changes the equation. I'm going to have to spend some time with it. I'm in a design phase now.

I think I'm also going to build a roughly 3' foot long model using ------- I'm not sure what. but I want rib formers for the model that are like my full size ones, splined in the middle so I can vary width and hinged at the sides so I can vary side flare. Formica makes a dynamite model side panel material but it's getting hard to find. Everybody is doing kitchen/bathroom counters with full thickness materials anymore (these days). I'll find something.

You are most welcome Sandy. Thank you for sharing all your knowledge. I found one item about the displacement calculations in Free!Ship that I overlooked. Hydrostatic calculations are done in longtons when using the imperial system so the weights I shared above for the various displacements are slightly undervalued. A longton is 2240 pounds and I was using 2000 pounds. So now that I am using the correct density for freshwater and the correct conversion for tonnage, the HD will draft 5.5" when loaded with 864-865 pounds and the Briggs will draft 5.5" with 896 pounds.

I have been reading the manual from version 2.6 while the Sourceforge / C-Net links are hosting v2.3. Google and install v 2.6 it has implemented a stability calculations module. The README detail the update history.

I am entering the Rogue Classic (Bob Pritchett's last boat) from Fletchers book.

This is very cool. I may just not know what I'm looking at so its probably in the tables above, but would any one be able to tell me how much the honky draws at 1,100 lbs or so? I ask because I am trying to work out the floor height for self bailing rower's footwell, and potentially passenger footwell too.

Scaling the Honkey up as I did in the thread called 3-D Models and assorted stats, the 17' version of the Honkey (59.9") bottom will sit right on the Briggs line. In the graph above, an 18' Honkey would be above the Briggs line as you surmise. BTW- Andersenpj in the post above is my old neighbor so I am guessing you two probably aren't in the same town since I know where you both live...

Pat offered to help me get my molasses brains around FreeShip about 10 days ago. But I was in Chicago. I'm back in the Bozeone now. Glued to my shop fly tying bench and keyboard. As usual. It's too cold to fish.

Samuel, I'm curious what you find for self-bailing deck height/seat height/gunwale height arrangement. I'm just not sure it's going to work out well with a boat that has both it's sides cut from a single 4'x16' piece of ply. I suspect the Honkey might be able to though. There are plenty examples of smaller decked boats, but self-bailing seems to be tricky to pull off correctly (and still be in a comfortable rowing position, without interfering with your knees....) I guess you could make pylons to raise the oarlocks if you need to..??

Please share some basic dimensions or a sketch of your side profile when you sort it out. I started to think about it with a standard McKenzie, but, then abandoned... Why bother, it's so simple, affordable, and capable, I'd just be bastardizing it. (--- stick with the plan ---)

RE: Not in the same town. Well it's too bad you and Pat are not in the same town! I have been saying that about Pat and for how long now Pat? 6 years? That has to end! Best guy around in my book!
-Mike